(133c) Thermal Characterization of Microalgal Biomass and Lipids Extracted Residual for Biofuel Production

This communication reports non-isothermal combustion kinetics of microalgal biomass before and after lipid extraction. The thermal decomposition experiments are conducted in a thermogravimetric analyzer (TGA) using air as combustion agent. The biomass samples are exposed up to 800^oC with different heating rates. The TGA analysis shows that the decomposition profiles of the biomass samples before and after lipid extraction follow different paths. The apparent activation energy of the oxidation reaction is estimated by fitting an iso-conversional model (Kissinger–Akahira-Sunose) with the experimental data. It is observed that at early stage of biomass combustion, the activation energy increase with increasing the conversion until reaching the maximum at almost a middle conversion stage. After that the value of activation energy decreases sharply. It is also found that the activation energy of lipid extracted biomass decomposition is significantly lower than that of the biomass sample.

Acknowledgments:

Authors like to acknowledge KACST for funding this work through the project NSTIP 13-WAT96-04.